The creation of an article with a low relief, three-dimensional image, also known as a bas relief, is conventionally performed by one of the following four methods. The first method involves creating an image by removing material from an article, for example, by sculpting. Alternatively, a machine may be employed to route, mill or laser away material leaving a desired three-dimensional topography. Duplication machinery, such as pantographs and multiple spindle machining centers can increase production rates, but are commercially limited to low volume production. The size of the resulting bas relief typically is limited by the dimensions of a duplication machine's operating range or bed size.
A second conventional method of producing a bas relief is via the use of a mold. Typically, a mold from which a bas relief is cast is made manually (e.g., by an artist). Molds are typically used in producing bas relief made from metal, clay, brick, and the like.
A third conventional method of producing a bas relief is via embossing. Embossing is a procedure where pressure is used to deform a material to create a three dimensional relief therein. This method may be used to produce bas relief in plastics, leather, cloth, sheet metal, clay, and the like.
A fourth conventional method of producing a bas relief is via direct deposition of polymer material on a surface, for example, under computer control. Polymer material may be applied as a liquid and dried or, alternatively, polymer material may be applied as a liquid and then polymerized (i.e., cured) with targeted energy.
Unfortunately, all of these conventional methods have cost and size limitations. In the case of direct creation, size may be limited by the machine used to remove material from an article to create a three dimensional topography. In the case of molding or embossing, the size of a bas relief is limited by the equipment involved. The cost of molds and embossing tools typically goes up exponentially as size increases, as does the size and cost of the machine necessary to employ the mold or embossing medium.